Primary Aldosteronism – Modern Concepts in the Diagnostic and Therapeutic Approach

Abstract:
Primary aldosteronism (PA) is the most common form of endocrine hypertension with a prevalence estimated to be around 8,8%among hypertensive patients. Cross-sectional and prospective studies have shown a prevalence of more than 5% in patients in primary health care and higher than 10% for patients in specialized centers.
Untreated PA might result in increased cardiovascular, nephrologic and metabolic complications.
Aldosterone adrenal hypersecretion is the main pathologic pattern in all subtypes of PA. Bilateral adrenal hyperplasia (BAH) and aldosterone-producing adenomas (APAs) are the two most common forms of the disease. The diagnosis of PA is usually elaborated using a 3-way step approach:
1. screening;
2. confirmatory test;
3. differentiation of primary aldosteronism subtype. The aldosterone/renin ratio is the most widely used screening method. Recently the attention has been focused on the development of new more sensitive and specific screening and confirmatory tests. Adrenal CT scanning with contrast isthe initial radiologic investigation in the workup of PA. Until now adrenal venous sampling has been used as the “gold standard” in thedifferential diagnosis between unilateral and bilateral aldosterone excess. The sensitivity and specificity of AVS (95 and 100% respectively) is
superior to adrenal CT – 78 and 75%, respectively. According to the latest guideline on PA management the extensive use of the invasive AVS method should be limited when there are conclusive clinical, hormonal and CT data evidence for Conn’s adenoma. Treatment of APAs is usually operative – adrenalectomy, while BAH is treated with medication. All patients treated pharmacologically should receive a mineralocorticoid receptor antagonist, that has been shown to block the deleterious effects of aldosterone.